Holly Hazlett-Stevens, PhD, is assistant professor of psychology at the University of Nevada in Reno, NV. She has conducted psychological research in the areas of worry, anxiety, and relaxation for the past ten years, which has led to the publication of twelve journal articles and five book chapters. She also coauthored New Directions in Progressive Relaxation Training with Douglas A. Bernstein and Thomas D. Borkovec. In 2004, she was listed in Marquis' Who's Who of American Women and Academic Keys Who's Who in Social Sciences and Higher Education. Michelle G. Craske, PhD, received her doctorate from the University of British Columbia in 1985 and has published over 100 articles and chapters in the areas of anxiety disorders and fear. She recently completed an advanced-level text, Anxiety Disorders: Psychological Approaches to Theory and Treatment. Currently, she is professor of psychology at the University of California, Los Angeles, and director of the UCLA Anxiety Disorders Behavioral Research Program. She serves on the DSM-IV Anxiety Disorders Workgroup Subcommittee; is a consultant to various national organizations in their efforts to develop and disseminate practice guidelines for panic disorder and other anxiety disorders; and has been awarded NIMH/NIH funds for the study of anxiety disorders. Her research focuses on furthering the understanding of fear and anxiety and in developing more effective treatments for the anxiety disorders.